The first area of the proposed research is directed at elucidation of the mechanisms and products of electrochemical oxidation of purine nucleosides and nucleotides, polynucleotides and nucleic acids. Such reactions and mechanisms will provide valuable information on the redox behavior of these compounds which should result in a greater understanding of the function and reactions of purine derivatives in biological systems. The second area is directed at developing an understanding of the behavior of purine derivatives, particularly polynucleotides and nucleic acids, at charged electrode-solution interfaces especially at electrical potentials where electron-transfer reactions do not occur. A large number of biochemical reactions are controlled by or associated with the behavior of molecules adsorbed or associated at charged interfaces. The interfacial adsorption of such purine derivatives will be studied by d.c. voltammetry, a.c. and phase- selective a.c. voltammetry and polarography, double layer capacitance measurements, electrocapillary, electrochemical ellipsometry and spectroelectrochemical experiments. It should be possible via these studies to evaluate the effects of electrical potential on the adsorption, orientation and intermolecular association of purine derivatives and allow formulation of surface- structure-electrical potential relations. This information should have a direct bearing on understanding the interfacial properties of purine derivatives at biological interfaces in living systems.